Grant
And all who have not heard a difference or very little when direct mechanical coupling their power amps.
A short story. 1998 and having owned a Essence power amp for a few years and knowing the builder Dale Pitcher [now of Intuitive Designs}and the amps general layout. Alex Gibson the designer of FMS cables told me to forward my speaker cables to Brent Riehl in Lincoln to have them re-wired shotgun style in hopes of producing more bass slam. Brent as it happened designed the original Audiopoint for use with Dale's amp in mind . The Essence amp in Corian had potted power supplys on a single board laying flat on the chassis bottom. In discussion with Brent, this of course came up and I was sent 3 Audiopoint 1.5 APs. These points were to be threaded into the 3 inscribed factory ready receptacles,lifting the power supply away from the main chassis and then coupling the supply to mechanical gound. My self installing the 3 points under a 120 pound amp all the while trying to thread them into a floating power supply was about to kill me. The pay off was big time in every way. The stage size and clarity increase was amazing and huge. The very reason I purchased this amp over many others became even more apparent with the installation of the three coupling points.
The use of the points this first time was under a power amp, directly coupled to the huge power supply inside. Since this first encounter I have direct coupled almost every power transformer and almost as many power supply capacitors, always with a positive audio result. I have performed the latest upgrade to my Wyred4Sound SE preamp removing the steel mounting bolt holding down the transformer and replacing with non ferrous brass and remounting on .2 audiopoints. Result was greater speed and detail.
Looking back in time now I have gleaned that especially a large mass as a power amp it is most imperative to direct couple the power supply mechanically and better yet couple it independently from the amplification circuit. If not the power supply resonance will pollute the wide bandwidth circuit. The power supply always comes first before the circuit it supplys. The supply is the greatest of resonance offenders and needs to be corrected first and most effectively interior and then exterior. Perhaps this in part is why the difference in improvement was not as large as one may have predicted. Tom
